1. Field of the Invention
The present invention relates to an accessory of a camera which is provided separately from the camera and also relates to a transmitter-receiver system of a camera for informing the photographer of an operational state of the camera.
2. Description of the Related Art
When a picture is taken with a camera with its self-timer in operation, the shutter is generally released when a predetermined period of time (e.g., 10 seconds) elapses after the release button is depressed. A subject which is to be photographed needs to stay still upon the shutter being released to prevent the image of the subject from becoming blurry. Furthermore, since the photographer is usually apart from the camera when taking a picture with the use of self-timer, it is necessary to inform the photographer of the state of an operation of the camera (e.g., whether or not the self-timer is in operation and/or when the shutter is released) in any certain way. For this reason, in a conventional camera having a self-timer, the camera is usually provided with a light emitter (generally an LED) for emitting light (which is usually turned ON and OFF) and/or a sound generator for delivering audible signal to let the photographer know that the self-timer is in operation.
In a camera having a self-timer provided with a function of informing the photographer that the self-timer is in operation by emitting light, the photographer cannot recognize whether the self-timer is in operation unless the photographer keeps an eye on the camera. In a camera having another type of self-timer provided with a function that informs the photographer that the self-timer is in operation by delivering an audible signal, such a self-timer can be inappropriate if used in certain areas where making sound or noise is not preferable (e.g. an art museum or an area for bird watching).